In the field of electronic, a clock signal is used, like a metronome, to coordinate actions of a circuit. Computer retailers, for instance, often draw attention to the frequency of the clock rate in a given processor in order to advertise the performance of a computer.
Clock signals are also widely used in communication circuits. Many modern mobile communication devices may incorporate multiple communication standards. For instance, many modern mobile telephones include standards such as the Global System for Mobile Communications standard (GSM; also known as 2G), the Universal Mobile Telecommunications System standard (UMTS; also known as 3G), the Global Positioning System standard (GPS), the Institute of Electrical and Electronics Engineers' 802.11 series of standards (sometimes also known as Wi-Fi or WLAN), the Bluetooth standard, and the Long Term Evolution standard (LTE). These various standards may often require unique clocking requirements. Thus clock subsystems are found in various communication standards as function blocks, and may impact overall system costs.